Re: Common P2P Identifiers
>>>>> "Z" == Zane Thomas <zane@...> writes:Z> If I got a collision under those conditions I'd frame it.
>> For SHA-1 (160 bits) it would take 2^80 random documents to
>> have even a 50% chance of collision between the hashes of any
>> of them.
Seems to me I've heard this argument before. DNS, XML elements ...
What if, say in 2125, the galactic Internet started showing up more
collisions than we can frame? Couldn't we just introduce name spaces?
It seems counter productive to exhaustively plan for even the remote
contingency; we can drive off that bridge when we get to it.
Gary Lawrence Murphy <garym@...> TeleDynamics Communications Inc
Business Innovations Through Open Source Systems: http://www.teledyn.com
"Computers are useless. They can only give you answers."(Pablo Picasso)
- blanu said:
> An authority is necessary for both the algorithm and the text used. TheActually, the dictionary is only needed for creation of names. I believe
> security of this scheme is based on the security of the signatures used
> to verify the algorithm and text which is distributed.
that v.01 of the algo required the input text to be carried around,
because names mapped to numbers via their array index, but the .02 version
does mod 256 against a hash to get the corresponding number.
I've noticed the same pattern with other schemes. That is, generating new
names is _much_ more expensive than decoding them, and the input text is
only needed at encoding time. Any mapping algorithm that has this feature
is a hell of a lot more useful than otherwise, because a decoder should be
able to work in embedded devices.